A common problem at construction sites is the lack of accessibility to electrical power throughout the site. Electrical power is normally supplied by the utility company to a single point at the site. From there, power cords in the form of extension cords are run as needed to different locations throughout the site. This leads to the existence of a large number of power cords snaking throughout the area and the cords often become damaged or disconnected.
To protect the coupling area between two extension cords from damage and/or inadvertent disconnection, a number of housing-type devices have been invented that cover the area of the coupling. For examples of such devices, see U.S. Pat. Nos. 2,464,893, 3,281,755, 3,014,194, 3,344,393, 4,143,934, 4,643,505, 4,998,891, or the inventor's prior U.S. Pat. No. 4,911,654.
Prior art protective housings normally comprise a central cylindrical tube that surrounds the coupling area between two extension cords. The tube is normally composed of either one or two parts and includes a fastening structure that unites the housing around the electrical coupling. In some cases, a gasket or plug will be located proximate end portions of the housing to prevent moisture or dirt from entering the housing and affecting the electrical connection.
The prior art protective housings, while accomplishing their intended goals, suffer from certain failings.
One of the primary reasons for using a housing is to prevent water or moisture from reaching the plug and socket connection. In the prior art devices, the design of the seals and how they interact with the housing often results in leakage through the seals. Water can then collect within the housing and cause a short-circuiting of the electrical connection.
The manufacturing costs to produce the prior art devices are prohibitive in most cases. Complicated housing shapes are used that have extremely tight tolerances to achieve the necessary protective qualities of the devices. In addition, the manufacture of most of the prior art housings often entails multi-step machining operations and the joining of dissimilar materials. All of these factors lead to high costs that have made this type of product unsatisfactory for most common usages.
The tight tolerances and complexity of the prior art units also adversely affect their durability. For many devices, after repeated use, the units become difficult to assemble and the worn sealing surfaces further exacerbate any problems with leakage into the housing.